Saturday, August 22, 2009

Striped mystery beetle

I found this bug while I was raking leaves. I put him on a desert mallow for safe keeping. I have no idea what species this is.


Update: Icesign adds this link:

Friday, August 21, 2009

Color on the Web

Several years ago I killed the grass and put in a native plant garden. This garden continues to surprise me. In this case, it was the color transmitted through a dry spider web that amazed me. I emphasize that there was no moisture to create the irridescent effect. I hope the photos below show on your computer the colors I saw. Click the photos to see the colors better. I made no enhancements to the photos.

And last... no butterflies were harmed in the taking of this photo:


Sunday, August 9, 2009

Crepuscular and anti-crepuscular rays

Crepuscular rays are the beams of light we see near sunrise or sunset when clouds or mountaintops are well-positioned to cast shadows or provide gaps that beams of light shine through. (Note that the beam radiating from the above photo at about 1:00 shows a light ray that is then superceded by a shadow.) I have read that there are anti-crepuscular rays too. These are the rays you'd see if you looked in the opposite direction. I haven't noticed any till recently, when I saw these:

These were barely discernable, so below I enhanced the contrast to make them obvious. I made no other changes:

The illusion of separating or converging beams is a great reminder of how perspective affects perception. The rays and shadows are parallel, just as with meteors in a meteor shower, but they give the impression of radiating from a single point.
As much as a look at this crepuscular ray, I can't convince myself into seeing it as a horizontal beam:

Thursday, August 6, 2009

Venn diagram, field of view

OpenMind (see blog roll) is inviting charts.